To assess the role of graded treadmill exercise testing in evaluating patients with aortic regurgitation, 37 asymptomatic patients were evaluated preoperatively. Patients with echocardiographic evidence of severe left ventricular (LV) systolic dysfunction (functional shortening less than 25% and LV end -systolic dimension greater than 55mm) exercise as well as those with normal LV function. Exercise performance did not correlate with hemodynamic data and was not predictive of either operative deaths or late postoperative deaths from congestive heart failure. Exercise testing is thus an insensitive method with which to follow patients to determine the optimum time for aortic valve replacement.